06/17/2023
LAVENDER (lav) CAN MAKE LITTLE MISTAKES
Lavender is a true dilution (as ink in water) of both red and black (or blue, choc, dun etc) in the sense that less pigment enters the feather compared to when no lav is present.
Lavender is autosomal (the same in both sexes) and recessive, one dose (lav/Lav+) does nothing. The gene 'lav' makes it almost impossible for pigment to move further from the pigment-producing cell to the keratin cell where the feather is formed.
Pigment: black and red gets stuck and only a few pigment granules manage to bypass the traffic jam in the pigment cell and still get through to the feather.
Unlike other 'dilutions', the colour of the pigment is not changed. That means: red stays red, black stays black.
If a change from the virgin black or red was present, for example blue or choc or dun, or mahogany for red pigment, it will still be present. Only the amount of pigment entering the feather is much less when lavender is present. The pigments themselves are still 'full of colour', as they would previously enter the keratin.
However, sometimes the pigmenttrafficjam dissolves and the normal amount of pigment can 'sort of' enter the keratin. That's why you see transverse stripes in the feathers of lavender chickens, suddenly some more pigment could enter the keratin. Why? Because that's how lavender's pigmenttrafficjamming works. You know chickenparts grow mostly at night... bones do...
In the photo of the shoulder of an isabel or lavender-coloured mille fleur'ish c**k, you can see that lavender was unable to trap red pigment.
I am sure there are more interactions between lavender and other genes that cause a slightly different phenotype than expected. An example might be lav and B (cuckoo), or lav and I (dominant white). With such combinations, you might see more pigment fuzziness compared to simple genes that don't affect pigment delivery from pigment cell to keratin in terms of timing or the shape of the pigment itself.
Simple explanations on how (colour) genes work: www.chickencolours.com - Genetics of chicken colours book available in several (not all) languages.